by Kaity C
Native plants are making a comeback. There are two native wildflower meadows on Randall’s Island, and our Hellgate Wildflower meadow recently received a generous upgrade from a group of volunteers from the accounting firm Ernst and Young. I am inclined to plant natives, have seeded them in all the gardens where I have worked, and have gone on tours of native habitat gardens. And yet, when the volunteers were here and one asked about the reasoning behind planting wildflowers, I began to explain and realized I had internalized a love for natives but lost my grasp on the knowledge and evidence supporting their use. Change comes from a combination of understanding and fashion. On a superficial level, fashion is great for driving change. But understanding is what creates lasting change. “Sustainability” is a very fashionable word that can be bandied about without a true understanding of its origins and implementation, and I confess my understanding of natives became superficial over time. I’ve consulted a few resources on native plants here to re-educate myself and to remind others about why native plants deserve our attention.
1. What is a native plant?
There are varied opinions regarding this question. Generally, native plants are those found growing locally before the introduction of other plants from distant countries. However, in landscapes shaped by agriculture over thousands of years, this distinction may be arbitrary. In the United States, native plants are often defined as plants that were growing before contact with Europeans.
2. Are all native plants good and are all non-native plants bad?
Not necessarily. Some native plants are ideally suited to the local environment, whereas other natives are so successful that they dominate a planting and reduce the diversity of the whole area. Helianthus tuberosus (one common name: sun choke) is native to this region and also aggressive. In the Hellgate Wildflower Meadow, which was conceived to showcase the abundance and diversity of this region’s wildflowers, sun choke occupies large patches and could out-compete most of the other wildflowers if given the chance. In late summer, Eunyoung dispatched the whole crew to pull up the sun choke in an attempt to reduce their spread.
Non-natives can be invasive bullies, but many are ideally suited to gardens, despite their distant origins. Although I don’t know any gardener today who would deliberately plant Japanese knotweed or bindweed, there is a large class of common gardening plants that are non-native but are naturalized. Many of these ornamental, non-native plants cannot reproduce or spread readily without continued human help. Some ornamental, naturalized plants used in the gardens at Randall’s include: Muscari and Brunnera ‘Jack Frost’ and Echinops bannaticus ‘Taplow Blue’. Many non-native plants play an important role in supporting local biodiversity.
3. Yes, native plants are back in fashion. But besides being fashionable, why plant natives?
Native species have been adapting to local conditions for thousands of years. They have had longer to adapt to the soil and the climate, and they plan an invaluable role in supporting biodiversity.
Even modest increases in the native plant cover significantly increases the number and species of breeding birds, including birds of conservation concern. As our forests and natural areas continue to disappear under pavement, gardeners have the potential to play a crucial role in saving biodiversity.
Sense of place: The New York area has its own distinct assemblage of native plants. We are not obliged to create uniform national gardens of begonias, impatiens, and mums!
Ease of care: When installed in the appropriate site, natives require less maintenance than their exotic alternatives. Once established, they usually need less water. Having evolved with the area’s insects and diseases, they are less likely to need fertilizers or pesticides.
Habitat loss = species loss: There is a one-to-one correspondence between habitat destruction and species loss. In Delaware, for instance, state ecologists say that 40 percent of all native plant species identified in 1966 are threatened or extinct; 41 percent of native birds that depend on forest cover are rare or absent.
For many locally rare animals, native plants are essential to their survival. For example, the Federally-endangered Karner blue butterfly feeds exclusively on wild blue lupine, both of which are native to New York State. Although you may see our native insects visiting exotic plants, they are not able to sustain themselves from exotics. You will certainly see butterflies atop the blossoms on Butterfly bush, native to China, but you will only see adults who can sip the nectar. The plant cannot be eaten by the butterfly larvae.
Added beauty: New York City has hundreds of native species. These attractive plants meet every horticultural need from ground cover to attractive foliage and hardy blooms, and all ecosystem layers: ferns, wildflowers, vines, shrubs, and trees. A native garden can offer year round beauty and interest.
Preserve natural heritage: Our local biodiversity has diminished in the exotic invasion. Some introduced garden plants, like dame’s rocket, Oriental bittersweet, privet, and purple loosestrife have overtaken our landscapes. Planting natives is our only means to reclaim the landscape.
Cleaner waterways: Native grasses and wildflowers provide excellent erosion control. Increased biological diversity encourages rainwater to enter the soil. Monocultures of ground cover such as lawn create high levels of water runoff, thus encouraging local drought and polluting waterways during storm
events.
Working here has helped me see how Eunyoung and Phyllis have applied information about natives to the unique conditions at Randall’s Island. They have chosen plants that suit the local environment here without dominating it.
Some excellent resources for native plants:
Bringing Nature Home. (2008). Tallamy, Doug. Timber Press.
A Guide to Native Plants of the New York City Region (2007) New York City Department of Parks & Recreation. Gargiullo, Margaret B.
Manual of Vascular Plants of Northeastern United States and Adjacent Canada Second Edition (1991) The New York Botanical Garden. Gleason, Henry Ph.D., Arthur Cronquist, Ph.D.
Native Plants of the Northeast A Guide for Gardening and Conservation (2005) Leopold, Donald, J.
Native Species Planting Guide for New York City and Vicinity (1993) Natural Resources Group, City of New York Parks & Recreation. Luttenberg, Danielle, Deborah Lev, Michael Feller.
Wildflowers in the Field and Forest. A Field Guide to the Northeastern United States. (2006). Clemants, Steve and Carol Gracie. Oxford University Press.
Rosenzweig M. L. 2001. Loss of speciation rate will impoverish future diversity. Proceedings of the National Academy of Science. USA 98, 5404–5410
By Laura Merli
The seeds used were originally harvested from Randall’s Island’s current wildflowers. The weight of the seed bombs ensure that the 
seeds will grow in the places carved out for them, rather than hopping a ride on the wind elsewhere. As they begin to grow, the compost will provide nourishment.
Gardens Randalls 